If nothing else, President Xi Jinping is known for his pursuit of order. So how far the Chinese president’s attack on the "disorderly expansion of capital” will go has emerged as a defining question for investors trying to navigate the country’s wave of regulatory crackdowns.

Since first appearing in a Politburo readout in December, the phrase has been employed by government agencies and researchers to explain actions against technology moguls, celebrities and private tutors that fueled a $1.5 trillion stock rout last month. The slogan, like "common prosperity,” is among several Xi-isms feeding concerns that China is tilting away from free markets and back toward more ideologically driven centralized planning.

Its meaning, however, is even more mysterious than its egalitarian-sounding cousin. The exact words "disorderly expansion of capital” have appeared only five times in documents directly connected with Xi, according to a Bloomberg News review of nine years of the leader’s speeches and meetings. All mentions came in the past 10 months.